GPT-5.5 System Card
OpenAI has released GPT‑5.5, a new model aimed at complex real‑world tasks such as coding, research, and document creation. The model reportedly understands tasks earlier, requires less guidance, uses tools more effectively, and persists until completion. OpenAI conducted extensive pre‑deployment safety evaluations, including targeted red‑teaming for advanced cybersecurity and biology capabilities, and gathered feedback from nearly 200 early‑access partners. The release includes the strongest safeguards to date, with a separate evaluation for GPT‑5.5 Pro, which uses parallel test‑time compute. The system card was updated on April 24, 2026, adding details on safeguards for API deployment.
The Core Development
GPT‑5.5 is a new model designed for complex, real-world work, including writing code, researching online, analyzing information, creating documents and spreadsheets, and moving across tools to get things done. Relative to earlier models, GPT‑5.5 understands the task earlier, asks for less guidance, uses tools more effectively, checks it work and keeps going until it’s done.
We subjected the model to our full suite of predeployment safety evaluations and our Preparedness Framework, including targeted red-teaming for advanced cybersecurity and biology capabilities, and collected feedback on real use cases from nearly 200 early-access partners before release. We are releasing GPT‑5.5 with our strongest set of safeguards to date, designed to reduce misuse while preserving legitimate, beneficial uses of advanced capabilities.
We generally treat GPT‑5.5’s safety results as strong proxies for GPT‑5.5 Pro, which is the same underlying model using a setting that makes use of parallel test time compute. As noted below, we separately evaluate GPT‑5.5 Pro in certain cases because we judge that the setting could materially impact the relevant risks or appropriate safeguards posture. Except where noted, the results in system cards describe evaluations we ran in an offline setting.
Strategic Perspective & Ecosystem Impact
This card was updated on April 24, 2026, to include additional information about safeguards for the deployment of GPT‑5.5 and GPT‑5.5 Pro in the API.
Why it matters
The release of GPT‑5.5 signals a continued push toward more capable, task‑oriented AI systems, while highlighting the importance of robust safety testing and safeguards in high‑impact models.